Perception minus expectations equals satisfaction.
I believe the first time I heard this was in reference to Disney World.

Disney's customers would spend hours waiting in line for a 2 minute ride. They would enter the line really excited about the ride (high expectations). But at the end, after waiting more for two hours, they felt like it was a waste of time (low perception).

So Disney had two choices:

Improve Perception (create a better ride/create more rides to reduce demand/let fewer people into the park.) Or...

Lower Expectations (make it very clear upfront what the customer was getting into.)

You've already guessed that Disney went with the second option -- they lowered expectations.

They simply added a sign at the end of the line that would tell each customer approximately how long they would have to wait (I heard that they even added a few minutes to these estimates just to be sure that expectations were really low).

This was a brilliant (and nearly free) solution to a big problem. The net effect was that satisfaction increased because expectations decreased -- the perception of the ride itself stayed the same.